Just what Elena Rybakina needed to start the second set, a relatively comfortable hold to 15.

Coco Gauff gets it to 15-15 but Rybakina soon shuts down any thoughts the American might break with a dismissive forehand, smoked into the corner.

Thanks, Emma.

How impressive was Coco Gauff in that first set?

Elena Rybakina will be world number one come Monday but she's got it all to do if she's to have a nice, shiny US Open trophy as well.

Can Coco Gauff see this out, or will Elena Rybakina find an answer?

To take you through the rest of this match, here's Sam Drury.

Image source, Getty Images

Coco Gauff is moving with such freedom, none of the nerves we saw yesterday against Mirra Andreeva are on show.

A smash winner puts her 30-0 ahead, then she picks up what seemed a definite Elena Rybakina winner with a brilliant baseline rescue before Kazakh nets.

Three set points... Gauff needs only one. Outstanding.

Coco Gauff has hit more winners and points receiving, while committing fewer unforced errors. She is ahead on just about every metric, emotional and statistical.

Elena Rybakina however gets a needed boost with a hold of serve. Gauff must serve for the set.

The crowd are firmly in this game, cheering every Gauff point.

Elena Rybakina's team courtside try to offer advice and encouragement, they know she will be fighting an uphill battle from this point.

But Gauff's tail is up. She chases back to retrieve a Rybakina lob, wins the point, and wins the game to love to consolidate her break.

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A high quality return from Coco Gauff sets the tempo for a rally she wins, gaining more acclaim from the partisan crowd.

In the rallies, Coco Gauff seems to just about have the advantage so far - her aggressive style is working.

Elena Rybakina tries to respond by coming to the net, but a tentative backhand volley is poked long. Break point Gauff.

Second serve... loose... Rybakina fires wide! First blood to the former champion.

So far the players have shared 14 unforced errors, a little scrappy. Nine of them have come from Elena Rybakina.

A look of frustration from Gauff as another first serve drifts wide on advantage - then as she tries to go big with the second serve, she misses down the middle. Double fault, back to deuce.

But then a roar from Gauff as she plants an ace! Risk, reward.

And an unreturned serve sees Gauff hold, roundly cheered by the crowd.

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For the first and certainly not last time tonight, the umpire has to tell the crowd to calm down as they get very excited at the prospect of Coco Gauff being about to serve.

Gauff maybe needs a boost to her serve so far - just seven of 17 first serves have found their mark so far.

And after being bested in a 14-shot rally, Gauff plants a messy backhand into the net. Deuce.

Oohs and aahs from the crowd as hawk-eye shows a serve from Elena Rybakina catches the line by a millimetre. Such tight margins.

She holds to 15 as Coco Gauff sends a return of serve into New Jersey.

In her quarter-final yesterday, Coco Gauff's 22 winners were vastly outnumbered by 42 unforced errors, including 12 double faults. She lost the opening set in 26 minutes, before having to battle through the long way around.

Early days of course, but the signs so far are that we are seeing a more familiar Gauff tonight.

Coco Gauff saved two match points as she fought from a set down to beat Mirra Andreeva in the quarter-finals. She knows how to battle if she needs to.

And she may have to again tonight, as an aggressive forehand return on the front foot from Rybakina beats Gauff all ends up. 30-30.

But the Kazakh follows that with a backhand wildly wide, before Gauff produces an unreturnable second serve at 99mph.

Rybakina holds. An early settler.

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Elena Rybakina is having a historic 2026. The Australian Open champion, and she's about to be the first tennis player of any gender from Kazakhstan to become world number one.

Adding a US Open title to that roll of honour would be quite the achievement.

It won't be easy though. A forehand winner on the rise by Coco Gauff makes it 30-30 - before Rybakina puts a backhand in the net. Early break chance for the American.

But she cannot take it, as the tall Rybakina rescues a ball from near her feet for an unreturnable backhand. Deuce.

Sam Drury
BBC Sport

Great Britain's Neal Skupski and his American partner Christian Harrison are through to the US Open men's doubles final after beating top seeds Henry Patten and Harri Heliovaara.

The Australian Open champions secured a 7-6 (7-4) 6-2 win in an hour and 23 minutes and are yet to drop a set at this year's tournament.

Liverpool-born Skupski, 36, is hoping to claim his fifth Grand Slam title and third in the men's doubles.

After success at Wimbledon in 2023 with Wesley Koolhof and in Australia earlier this year alongside Harrison, Skupski once again has a maiden triumph at Flushing Meadows in his sights.

He and fellow Briton Joe Salisbury missed three championship points when they lost last year's final.

Germany's Kevin Krawietz and Tim Puetz are also through to Saturday's final after a 6-3 6-4 victory over three-time US Open men's doubles champions Salisbury of Great Britain and Rajeev Ram of the United States.

The match proved to be the last of a hugely successful career for 42-year-old Ram, who retires having won six Grand Slam doubles titles - including three in succession in New York alongside Salisbury in 2021, 2022 and 2023, as well as two Olympic silver medals.

A slightly shaky start by Elena Rybakina, with successive backhand unforced errors.

Coco Gauff takes full advantage with an ace to seal the opening game.

Image source, Getty Images

Can Elena Rybakina set up a final against top seed Aryna Sabalenka - a first US Open final between the two top-ranked players since 2013?

Or will Coco Gauff ensure the US Open crowd have a home hero to cheer on Saturday?

Away we go.

Former US Open champion Gauff will have the home crowd's backing tonight at Arthur Ashe Stadium.

The 22-year-old American, who won the Flushing Meadows title in 2023 but suffered fourth-round exits in the following two years, said she has a different perspective to this year's tournament.

"Sometimes you're just so focused on the now, now, now, because you want it now, and obviously you want to take advantage of your opportunities," she said.

"In the grand scheme of things, [I'm] definitely sitting here in a different mindset and perspective than I was last year.

"It inspires me a little bit more to keep working, as I see how much I have improved in a year."

Gauff leads the head-to-head 2-1, but Australian Open champion Elena Rybakina fought back from a set down to triumph in last month's Canadian Open semi-finals.

"I'm going to have some aces hit on me and some winners hit on me, but I'm going to keep fighting and give it my all. That's all I can do," Gauff said.

Coco Gauff - who it is fair to say has her game face on, no hint of a smile cracked - wins the toss and will serve first.